The invention relates to cooling system units. In particular, the invention relates to providing controlled cooling for a computer system for use in environments and applications that place high demands on system reliability, for example in the telecommunications industry.
Deregulation and privatization is causing unprecedented competition in the worldwide telecommunications market. This climate of fierce competition has meant that service providers must introduce new, more sophisticated and user-friendly services at an accelerated pace to retain or attract subscribers, while not compromising traditional telecommunications company (telco) service quality.
These pressures of competition have also placed high demands on Network Equipment Providers (NEPs). Traditionally, NEPs have designed, built and supported proprietary computing equipment, as the strict telco requirements could not be met by the commercial computing sector. Those requirements include the so-called Telcordia Technologies Network Equipment Buildings Systems (NEBS) tests. However, due to the lead times required to design and test such proprietary equipment, and the cost of supporting such equipment, there is a need to find another route, at least for the supply of the more cost and performance sensitive sectors within the telco industry.
A major concern of the telco sector is the reliability of systems under environment conditions as set by the NEBS tests.
In order to keep up with the ever-increasing demands of the telco industry, and in order to provide equipment at reasonable cost and within reasonable time scales, it would be desirable to use as many off-the-shelf computer system components as possible, rather than having to design and test each system in its entirety from scratch. For example, it would be desirable to select components designed for the commercial computing sector. However, such equipment is typically not designed with the stringent requirements of the telco industry in mind.
Accordingly, it is an aim of the present invention to address the provision of cost-effective equipment that can meet technical demands of the telco environments, for example as regards providing reliable operation under adverse operating temperatures, while also meeting the modem commercial demands of that environment.
Particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. Combinations of features from the dependent claims may be combined with features of the independent claims as appropriate and not merely as explicitly set out in the claims.
In accordance with one aspect of the invention, there is provided a fan control module for a system unit. The fan control module comprises power outputs for supplying power to a plurality of fan. It also includes a temperature sensor for giving a temperature signal. It further includes a control unit connected to receive the temperature signal. The control unit includes preprogrammed control information for determining power signals to be supplied to each of the fan units for controlling the speed thereof dependent upon the temperature signal.
The provision of a separate fan control module for controlling the fan units in a coordinated manner enables reliable and effective cooling of the system unit under widely varying parameters. It also means that existing system components can be employed in harsher temperature environments than they were originally designed for, without needing a complete redesign thereof.
Moreover, where the fan control module includes one or more power inputs from a power supply that is also used to power the other components of the system unit, the fan control module can be provided with electrical noise isolation circuitry to isolate other components of the system unit, from electrical noise generated by the fan units.
In order to limited the power handling requirements of the fan control module circuits, in an embodiment of the invention the fan control module can be logically split into two parts. A first part controls a first pair of fan units and the second part controls a second pair of fan units. Each part of the fan control module can be provided with respective inputs, outputs and control units. The control information programmed in the control unit of each part can be identical. Preferably, one temperature sensor is be employed by both parts to provide a co-ordinated ramp for the fan speeds. Also, where more than four fans are provided, more than two fans per part could be controlled and/or more parts could be employed, as appropriate.
The fan control module is preferably configured on a single circuit board. This provides particular advantages where the fan control card is to be provided as an addition to a system. The temperature sensor is preferably mounted on the circuit board, although it could be placed at some another part of the system as appropriate. Preferably one temperature sensor is used as this facilitates the provision of a controlled and coordinated ramp up of the fan speeds. However, more than one temperature sensor could be used, if desired, with each temperature sensor providing respective signals and control of the individual fans being dependent upon individual temperature signals or a function of some or all of the temperature signals.
Preferably speed signals, for supply to an alarms module, are directed via the fan control module and a power distribution board. The fan control module does not process these signals, but the feeding of the signals via the fan control module enables an efficient wiring loom to be made, with a single bundle of wires and a single connector being connected to a fan unit.
In accordance with another aspect of the invention, there is provided a system unit including a fan control module, the fan control module comprising power outputs for supplying power to a plurality of fan units, a temperature sensor for giving a temperature signal, and a control unit connected to receive the temperature signal and including preprogrammed control information for determining power signals to be supplied to each of the fan units for controlling the speed thereof dependent upon the temperature signal.
In a particular embodiment the system unit is a computer system unit including at least one processor module. It may contain anywhere between one and four processor modules. This puts further demands on the cooling requirements, as these will vary in accordance with the number of processors present. Accordingly, the power supply signals output by the control unit can be made dependent upon to the number of processor modules present.
In accordance with a further aspect of the invention, there is provided a method of controlling cooling of a system unit, the method comprising:
a fan control module receiving a temperature signal from a temperature sensor;
the fan control module determining power outputs to the fan units for controlling the speed thereof dependent upon the temperature signal from the temperature sensor and preprogrammed control information for determining power signals to be supplied to each of the fan units for controlling the speed thereof.
In the particular embodiment mentioned above, the system unit is a computer server intended to be rack-mounted for a telecommunications application. It will be appreciated that this puts further strain on the cooling requirements, due to different possible configurations of adjoining equipment in a particular installation, and the possible proximity of other heat generating elements. It will be appreciated that the present invention provides particular and important technical advantages when applied to the adaptation of systems to meet the strict reliability and temperature requirements of, for example, telecommunications applications and that it is ideally suited to such telecommunications applications.